Cruisers Forum

Join CruisersForum Today

Thread Tools Rate Thread Display Modes
Old 27-10-2009, 18:08   #1
Registered User
Dollydagger's Avatar

Join Date: Jun 2009
Location: pacifica ,ca
Boat: challenger 32 '
Posts: 18
R12 to R134a

  • What it is it going to take to switch my cold plate to R134 its been sitting for awhile Everything seems to work except for the refridgerant No pressure in the lines. thanks everyone.

Dollydagger is offline   Reply With Quote
Old 27-10-2009, 18:13   #2

Join Date: Aug 2006
Posts: 205
Refrigerant doesn't wear out so first thing to do is find all the leaks. Then we can discuss what to do next.

Personally I recommend against conversions in areas where highest efficiency is a prerequisite. It is very unlikely the machine will work as well on 134 vs 12.

Your mileage may vary.

Noname1 is offline   Reply With Quote
Old 31-10-2009, 05:37   #3
Moderator Emeritus
GordMay's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 29,347
Images: 240
A word of warning, from Richard Kohlmann - Do not convert any hermetic compressors to 134a unless they are designed for 134a.

The new 134a refrigerant is not as efficient as R

KollmannMarine Boat Refrigeration Specialist

The older Danfoss BD 2.5 compressors use Freon R12 refrigerant and mineral refrigerant oil. Refrigerant 134a was not approved for these compressors because of its inability to mix with mineral oil and to change the oil to a compatible oil might destroy the insulation on the motor wiring.
There is one blended refrigerant, 409a, that can be used as a
replacement for R12 in BD2.5 compressors, but only in an emergency in cool climates. Warning, never mix refrigerants and always vacuum out the old before inserting a substitute.

Hermetically sealed compressors that are powered by alternating
current 110 or 220 volt may be filled with Alkylbenzene oil which is compatible with HCFC component refrigerants. Blended refrigerant 409a is recommended as a replacement for R12 in systems where the compressor contains alylbenzene oil.

Externally driven compressors, engine driven or those with large 12/24 volt motors are being converted from Freon R12 to 134a refrigerant. This also includes changing to a compatible Poly Ester conversion oil.

If you have one of these systems, contact the system manufacturer for their correct procedures for making this conversion.
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"

GordMay is offline   Reply With Quote
Old 31-10-2009, 11:43   #4

Join Date: Aug 2006
Posts: 205
Hence the reason to find all the leaks. If has sat flat for some time will have moisture and air in the system which causes lots other problems. If for example the leak is in the line set where rubbed against something perhaps with multiple deep vacuum and filter/drier changes it may be resurrected and while R-12 is expensive it may be the most cost effective way to solve the problem. Amazingly enough I can't begin to tell you how many times I have found a machine low or empty of refrigerant only to find previous "technician" couldn't be bothered to secure all service valve caps/bonnets and the refrigerant was lost due to poor work habits.

Please before anyone wants to chastise me for suggesting the use of R-12 consider first the environmental costs of manufacturing a new system to use R-134. The copper mine, the petrochemicals used, electricity. etc. R-12 available in the US is recycled so none new is made - here at least - lots made and used in "developing" countries.
Noname1 is offline   Reply With Quote

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Holding Plates- cleaning out r12 to replace with R134a Kapejna Plumbing Systems and Fixtures 2 06-06-2008 14:13
SOMEONE Help!! Racor R12 PUL Doghouse Engines and Propulsion Systems 4 30-05-2007 07:39

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 15:37.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.